Middle-deep geothermal well production and irrigation interchange system

Abstract

The utility model discloses a mining and irrigation interchange system for medium-deep geothermal wells, which comprises a 1 # well, a 2 # well and a 3 # well which are respectively and correspondingly provided with a first water delivery pipe, a second water delivery pipe and a third water delivery pipe. The first water delivery pipe is provided with 1 # and 2 # valves and is connected with a main pipe network water supply pipe; a third valve is arranged on the third water conveying pipe and connected with a main pipe network water return pipe; a first communicating pipe is arranged between the first water pipe and the third water pipe, one end of the first communicating pipe is behind the 2 # valve, and the other end is behind the 3 # valve; the second water conveying pipe is connected with a first communicating pipe, and a fourth valve and a fifth valve are arranged on the first communicating pipe; a second communicating pipe located in front of the first valve is arranged between the first water conveying pipe and the second water conveying pipe, and a sixth valve is arranged on the second communicating pipe. And a third communicating pipe with a 7 # valve is arranged between the first and third water pipes, one end of the third communicating pipe is arranged between the 1 # and 2 # valves, and the other end is arranged in front of the 3 # valve. The water taking well and the recharge well can be exchanged through valve switching, the investment is low, and the recharge efficiency is high.

Description

Technical Field

[0001] This utility model relates to the field of geothermal energy development and utilization technology, and in particular to a medium-deep geothermal well production and irrigation interchange system. Background Technology

[0002] Currently, geothermal energy development and utilization technology based on water intake and reinjection (hydrothermal technology) mainly adheres to the principle of "heat extraction without water consumption." This involves extracting geothermal water from intake wells, passing it through a heat exchanger, and then reinjecting it back into the same underground aquifer after passing through a reinjection filtration device. However, due to the presence of suspended particles in the geothermal tailwater and the high pressure, resistance, and small porosity of the geothermal reservoir during reinjection, blockages are common, resulting in low utilization rates and resource waste. Currently, it is difficult for geothermal wells to achieve proportional reinjection; one intake well requires at least two reinjection wells to ensure effective reinjection. Furthermore, to guarantee reinjection effectiveness and extend the lifespan of geothermal wells, it is often necessary to interchange intake and reinjection wells to improve geothermal utilization efficiency. However, existing geothermal energy development and utilization projects typically use a paired-well configuration. Achieving interchangeability between intake and reinjection wells requires significant initial investment, involves complex operations, and results in insufficient sand removal, leading to a short lifespan for the geothermal wells. Summary of the Invention

[0003] To address the aforementioned problems, this utility model provides a mid-deep geothermal well production and irrigation interchange system, specifically employing the following technical solution:

[0004] The medium-deep geothermal well production-injection interchange system of this utility model is installed between a geothermal well and a surface heat exchange device. The geothermal wells include well #1, well #2, and well #3. Well #1 has a first water supply pipe, well #2 has a second water supply pipe, and well #3 has a third water supply pipe. The first water supply pipe is equipped with valves #1 and #2 and is connected to the main water supply pipe of the surface heat exchange device. The third water supply pipe is equipped with valve #3 and is connected to the main return pipe of the surface heat exchange device. A first connecting pipe is installed on the first water supply pipe and connects to the third water supply pipe. One end of the first connecting pipe is located after valve #2 on the first water supply pipe, and the other end of the first connecting pipe is... After valve #3 of the third water supply pipe; the second water supply pipe is connected to the first connecting pipe, and valve #4 is located between the first and second water supply pipes, and valve #5 is located between the second and third water supply pipes; a second connecting pipe is connected to the second water supply pipe on the first water supply pipe, valve #6 is installed on the second connecting pipe, and valve #1 is located before the end of the second connecting pipe connected to the first water supply pipe; a third connecting pipe is connected to the third water supply pipe on the first water supply pipe, one end of the third connecting pipe is located between valve #1 and valve #2 of the first water supply pipe, the other end of the third connecting pipe is located before valve #3 of the third water supply pipe, and valve #7 is installed on the third connecting pipe.

[0005] A cyclone sand separator is installed on the main water supply pipe.

[0006] A recharge filter is installed on the main pipeline return water pipe.

[0007] The medium-deep geothermal well extraction and reinjection interchange system provided by this utility model has a simple structure and is easy to use. By switching valves, the extraction well and the reinjection well can be interchanged. The system shares a set of geothermal water desanding treatment, tailwater filtration treatment, and pressurized reinjection equipment for both the extraction well and the reinjection well, which can improve the desanding effect. It can achieve the interchange of extraction well and reinjection well without changing the main water supply and energy supply network, which can significantly reduce project investment, improve reinjection efficiency, and extend the service life of geothermal wells. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the structure of this utility model. Detailed Implementation

[0009] The embodiments of this utility model will be described in detail below with reference to the accompanying drawings. These embodiments are implemented based on the technical solution of this utility model and provide detailed implementation methods and specific working processes. However, the protection scope of this utility model is not limited to the following embodiments.

[0010] like Figure 1 As shown, the medium-deep geothermal well production-injection interchange system of this utility model is installed between the geothermal well and the surface heat exchange device. The geothermal well includes well #1, well #2, and well #3. Well #1 is equipped with a first water supply pipe 1, well #2 with a second water supply pipe 2, and well #3 with a third water supply pipe 3. The first water supply pipe 1 is equipped with valve #1 and valve #2, and is connected to the main water supply pipe 4 of the surface heat exchange device. The third water supply pipe 3 is equipped with valve #3, and is connected to the main water return pipe 5 of the surface heat exchange device. The first water supply pipe 1 is equipped with a first connecting pipe 6 connected to the third water supply pipe 3. One end of the first connecting pipe 6 is located after valve #2 of the first water supply pipe 1, and the other end of the first connecting pipe 6 is located at the third water supply pipe 3. After valve #3 of water pipe 3; the second water supply pipe 2 is connected to the first connecting pipe 6, and valve #4 is installed on the first connecting pipe 6 between the first water supply pipe 1 and the second water supply pipe 2, and valve #5 is installed between the second water supply pipe 2 and the third water supply pipe 3; a second connecting pipe 7 is installed on the first water supply pipe 1 and connected to the second water supply pipe 2, valve #6 is installed on the second connecting pipe 7, and valve #1 is installed before the end of the second connecting pipe 7 connected to the first water supply pipe 1; a third connecting pipe 8 is installed on the first water supply pipe 1 and connected to the third water supply pipe 3, one end of the third connecting pipe 8 is located between valve #1 and valve #2 of the first water supply pipe 1, the other end of the third connecting pipe 8 is located before valve #3 of the third water supply pipe 3, and valve #7 is installed on the third connecting pipe 8. To avoid introducing impurities into the water supply network of the ground heat exchanger, a cyclone separator 9 is installed on the main water supply pipe 4. In order to remove suspended particles from the geothermal tailwater, a reinjection filter 10 is installed on the main return water pipe 5.

[0011] In actual operation, this invention requires periodic monitoring of indicators such as water temperature, water level, and impurity content in various geothermal wells. Based on the monitoring results, the function of each geothermal well is determined; that is, one geothermal well is selected as the water intake well, while the other two are used as reinjection wells. The functional changes of the geothermal wells are achieved through valve opening and closing and pipeline switching. Specifically:

[0012] Mode 1: Well #1 is a water intake well, and Wells #2 and #3 are recharge wells.

[0013] In this mode, valves #1, #2, #3, and #5 are open, while valves #4, #6, and #7 are closed. Geothermal water from well #1 passes through valves #1 and #2, then through the cyclone desander 9 and the main water supply pipe 4 into the surface heat exchange device. After heat exchange, the geothermal tailwater passes through the main water return pipe 5, is filtered by the reinjection filter 10, and then reinjected into wells #2 and #3 through valves #3 and #5, respectively.

[0014] Mode 2: Well #2 is a water intake well, and Wells #1 and #3 are recharge wells.

[0015] In this mode, valves #1, #3, #4, and #7 are open, while valves #2, #5, and #6 are closed. Geothermal water flows from well #2 through valve #4, then through the cyclone desander 9, and finally through the main water supply pipe 4 into the surface heat exchange device. After heat exchange, the geothermal tailwater flows through the main water return pipe 5, is filtered by the reinjection filter 10, and then reinjected into wells #1 and #3 through valves #3, #7, and #1, respectively.

[0016] Mode 3: Well #3 is a water intake well, and Wells #1 and #2 are recharge wells.

[0017] In this mode, valves #2, #5, #6, and #7 are open, while valves #1, #3, and #4 are closed. Geothermal water from well #3 passes through valves #7 and #2, then through the cyclone desander 9 and the main water supply pipe 4 into the surface heat exchange device. After heat exchange, the geothermal tailwater passes through the main return water pipe 5, is filtered by the reinjection filter 10, and then reinjected into wells #1 and #2 through valves #5 and #6, respectively.

[0018] It should be noted that in the description of this utility model, terms such as "front", "rear", "left", "right", "vertical", "horizontal", "inner", and "outer" indicating orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

Claims

1. A system for interchanging between a medium-deep geothermal well and a ground heat exchange device, which is arranged between the geothermal well and the ground heat exchange device, characterized in that: The geothermal well comprises a No. 1 well, a No. 2 well and a No. 3 well, the No. 1 well is provided with a first water delivery pipe, the No. 2 well is provided with a second water delivery pipe, and the No. 3 well is provided with a third water delivery pipe; the first water delivery pipe is provided with a No. 1 valve and a No. 2 valve, and the first water delivery pipe is connected with a main pipe network water supply pipe of the ground heat exchange device; the third water delivery pipe is provided with a No. 3 valve, and the third water delivery pipe is connected with a main pipe network backwater pipe of the ground heat exchange device; the first water delivery pipe is provided with a first communication pipe connected with the third water delivery pipe, one end of the first communication pipe is arranged behind the No. 2 valve of the first water delivery pipe, and the other end of the first communication pipe is arranged behind the No. 3 valve of the third water delivery pipe; the second water delivery pipe is connected with the first communication pipe, and the first communication pipe is provided with a No. 4 valve between the first water delivery pipe and the second water delivery pipe and a No. 5 valve between the second water delivery pipe and the third water delivery pipe; the first water delivery pipe is provided with a second communication pipe connected with the second water delivery pipe, the second communication pipe is provided with a No. 6 valve, and one end of the second communication pipe connected with the first water delivery pipe is arranged in front of the No. 1 valve; the first water delivery pipe is provided with a third communication pipe connected with the third water delivery pipe, one end of the third communication pipe is arranged between the No. 1 valve and the No. 2 valve of the first water delivery pipe, the other end of the third communication pipe is arranged in front of the No. 3 valve of the third water delivery pipe, and the third communication pipe is provided with a No. 7 valve.

2. The system according to claim 1, characterized in that: The main pipe network water supply pipe is provided with a cyclone sand remover.

3. The system according to claim 1, characterized in that: The main pipe network backwater pipe is provided with a recharge filter.

Images